The robot controls the human limb by sending small electrical currents to electrodes taped to the person’s forearm and biceps, which allows the robot to command the elbow and hand to move. In the experiment, the person holds a ball, and the robot holds a hoop; the robot, a small humanoid, has to coordinate the movement of both human and robot arms to successfully drop the ball through the hoop.

The researchers say their goal is to develop robotic technologies that can help people suffering from paralysis and other disabilities to regain some of their motor skills.